Only send WM_PAINTICON and WM_ICONERASEBKGND to 16-bit windows (found

dlls/user/message.c

@@ -2278,17 +2278,8 @@ BOOL WINAPI PeekMessageW( MSG *msg_out, HWND hwnd, UINT first, UINT last, UINT f
 
     WIN_RestoreWndsLock( locks );
 
-    /* need to fill the window handle for WM_PAINT message */
-    if (msg.message == WM_PAINT)
-    {
-        if (IsIconic( msg.hwnd ) && GetClassLongW( msg.hwnd, GCL_HICON ))
-        {
-            msg.message = WM_PAINTICON;
-            msg.wParam = 1;
-        }
-        /* clear internal paint flag */
+    if (msg.message == WM_PAINT)  /* clear internal paint flag */
         RedrawWindow( msg.hwnd, NULL, 0, RDW_NOINTERNALPAINT | RDW_NOCHILDREN );
-    }
 
     if ((queue = QUEUE_Current()))
     {

dlls/user/painting.c

@@ -250,8 +250,7 @@ HDC WINAPI BeginPaint( HWND hwnd, PAINTSTRUCT *lps )
     WIN_ReleasePtr( wndPtr );
 
     if (lps->fErase)
-        lps->fErase = !SendMessageA( hwnd, bIcon ? WM_ICONERASEBKGND : WM_ERASEBKGND,
-                                     (WPARAM)lps->hdc, 0 );
+        lps->fErase = !SendMessageA( hwnd, WM_ERASEBKGND, (WPARAM)lps->hdc, 0 );
 
     TRACE("hdc = %p box = (%ld,%ld - %ld,%ld), fErase = %d\n",
           lps->hdc, lps->rcPaint.left, lps->rcPaint.top, lps->rcPaint.right, lps->rcPaint.bottom,

windows/painting.c

@@ -647,8 +647,7 @@ static HRGN RDW_Paint( WND* wndPtr, HRGN hrgn, UINT flags, UINT ex )
 
     if (flags & RDW_UPDATENOW)
     {
-        if (wndPtr->hrgnUpdate) /* wm_painticon wparam is 1 */
-            SendMessageW( hWnd, (bIcon) ? WM_PAINTICON : WM_PAINT, bIcon, 0 );
+        if (wndPtr->hrgnUpdate) SendMessageW( hWnd, WM_PAINT, 0, 0 );
     }
     else if (flags & RDW_ERASENOW)
     {
@@ -674,8 +673,7 @@ static HRGN RDW_Paint( WND* wndPtr, HRGN hrgn, UINT flags, UINT ex )
 		    dcx &= ~DCX_INTERSECTRGN;
 		if (( hDC = GetDCEx( hWnd, hrgnRet, dcx )) )
 		{
-		    if (SendMessageW( hWnd, (bIcon) ? WM_ICONERASEBKGND : WM_ERASEBKGND,
-                                      (WPARAM)hDC, 0 ))
+		    if (SendMessageW( hWnd, WM_ERASEBKGND, (WPARAM)hDC, 0 ))
                         wndPtr->flags &= ~WIN_NEEDS_ERASEBKGND;
 		    ReleaseDC( hWnd, hDC );
 		}

windows/winproc.c

@@ -2453,6 +2453,17 @@ INT WINPROC_MapMsg32ATo16( HWND hwnd, UINT msg32, WPARAM wParam32,
             *plparam = (LPARAM)next->hmenuIn;
             return 1;
         }
+    case WM_PAINT:
+        if (IsIconic( hwnd ) && GetClassLongW( hwnd, GCL_HICON ))
+        {
+            *pmsg16 = WM_PAINTICON;
+            *pwparam16 = 1;
+        }
+        return 0;
+    case WM_ERASEBKGND:
+        if (IsIconic( hwnd ) && GetClassLongW( hwnd, GCL_HICON ))
+            *pmsg16 = WM_ICONERASEBKGND;
+        return 0;
     case WM_PAINTCLIPBOARD:
     case WM_SIZECLIPBOARD:
         FIXME_(msg)("message %04x needs translation\n", msg32 );